[Hammarlund] questions for sp600-jx26?

[James A. (Andy) Moorer]

I will try to answer the ones that I can:
(I am no help with (1) and (2))

----- Original Message ----- 

> 3. I am trying to determine how "Free" my tuning dial is. If I give it a 
> really hard spin and let it free-wheel,
> I can get about 20-25 log numbers (in right dial).  Any one get about this 
> or more?
> I guess I had expected more range.

The only way I know to free it up is to disasssemble the whole mechanism and 
clean all the parts. When you put it all back together, it will spin like a 
champ.
One note: NEVER lubricate any of the SP-600 gears. The big, brass spinning 
weight moves the front dial by friction. Any libricant will slowly work its 
way
into that friction joint and make it so it never moves the dial again. 
(thanks for this tip to Les Locklear)

> 4. Did any sp600 ever come with rack handles? Mine does not but it seems 
> it would be useful when racking/unracking or even for use in a cabinet.

Not from the factory. They are useful to add, but they have to be able to 
take the 75 pound load.

> 5. Seems like mine has a whole added for a hardwired power cord (2 wire). 
> I know the current best practice is to
> change to a 3-wired (and I know this has to be done correctly. I will 
> check on this).  Has anyone tried to cut a
> hole to allow a standard IEC 3-prong receptacle for this? I may have my 
> terminology wrong, but its the standard
> receptacle used in, say, computers. Any one ever use the built-in 2 prong 
> receptacle? This seems dangerous to me
> as the power cord would have exposed male prongs that one could 
> accidentally touch when putting into the receiver.

I do that routinely. Cutting the right shape hole is a bit of a challenge. I 
use a sheet-metal "nibler" and a great deal of patience.
The original power cord picked up a ground from the round case of the 
connector. Unless you have exactly the right
connector, this is hard to do.

Do NOT operate it without the ground. I have measured 65 volts AC on the 
chassis of an ungrounded SP-600

> 6. Mine has an IF OUTPUT jack that *seems* original because the rear skirt 
> has the words "IF OUTPUT"
> engraved into it.  Anyone use this? I would like to use it for a 
> panadapter. Any one know if this is buffered and bypassed?

Yes, they all have that. It is buffered and bypassed and well isolated. It 
is good for an SSB adaptor, but not particularly good
for a panadaptor. The panadaptor feed needs to be picked off earlier in the 
chain. Most folks take it at the output of the
gate/2nd mixer. Of course, this means drilling another hole in the back 
panel. Hammarlund did this to some number of
SP-600JX17 models at the factory, but no JX-26 models that I know of.

> 7. I have yet to power it up or anything.  Will there be any detrimental 
> effect if I use an 8ohm spkr with it?
> I believe it had a standard 600 ohm output originally. Any quick and dirty 
> easy way to determine if it had been
> converted at any point? (I dont even know if this could be done with 
> something like a parallel resistor).

Connecting an 8-ohm speaker to it will eventually fry the output 
transformer. I guess you could put a 600-ohm resistor in series
with the 8-ohm speaker, but I don't think the volume would be very good.

I will sell you a brand-new military 600-ohm to 8-ohm transformer for $15 
(shipping included). Send me an address.

Best of luck!

James A. (Andy) Moorer
www.jamminpower.com